Night sights of the type in which an image of a dimly lit, viewed scene is intensified by an electron optical image intensifier tube can use an aiming reticle which appears in the field of view. The reticle can be of either the silhouette or illuminated type.
In the silhouette type, an opaque marking on a reticle appears as a dark mark against the scene background. The problem with this type is that, unless the scene is bright or the mark is so large that it obscures a significant part of the view, the mark can be very difficult to see.
Illuminated reticles comprise marks on a reticle which are illuminated by an internal light source and can therefore be made much smaller than the silhouette type. U.S. Pat. No. 3,960,453 issued to S. T. A. Svensson et al. discloses a conventional daylight telescope having a row of light emitting diodes (LED's ) which are projected into the field of view of the telescope to provide a moving light spot, the speed of which is adjusted to follow a moving target. While suitable for the purpose of providing a moving reference, the emitting area of each diode is too large to provide a desirably small aiming dot.
Another type of conventional illuminated reticle for a daysight includes a finely marked reticle which is illuminated by an internal light source. Such fine marks appear relatively dim against bright backgrounds which frequently appear in night sights.
Other illuminated reticle devices for daylight sights of the types disclosed in U.S. Pat. No. 3,320,671 to G. E. Rickert et al., and U.S. Pat. No. 3,645,635 issued to W. F. Steck use as reticles materials which fluoresce under ambient daylight and which obviously cannot be used in night sights.